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About JonCarleton

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    Star Forming

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  • Interests
    Music Performance, Fixed-wing and Gyroplane Aviation, Space, Computerism
  • Location
    Taylorsville, GA, US
  1. That galaxy is pretty large, but the Skywatcher 250P (254mm X 1200mm) with the SVBony305 has a very tight FOV. I struggle with that for really large objects, such as Andromeda Galaxy. I have tried a .5 reducer, but it causes focus issues and probably needs an extension tube. There was a bit of cropping for drift between frames, but not much. I'd say less than 5%. I did shave a bit off the left side for centering, but again, very minimal. I also bined X4 the entire image, but that would not increase the "fill" of the galaxy in the frame. Thank you for your kind comments.
  2. I finally got around to processing some of the stuff I have been shooting. Here's a whirlpool galaxy: Image captured as 100, 1.5 second @ 50% gain subs with the SVBONY305 and AstroDMx_Capture software. Processed with Siril (stacking), StarTools (image clean-up, color balance), then GIMP (sizing and cropping) all in Linux. Darks, Bias & Flats were not used. Scope was a SkyWatcher 250P with Synscan, however, tracking was done with INDI indi_skywatcherAltAzMount driver and no guide scope. Synscan GOTO was not used.
  3. Looking good! You have come a long way in a very short time. You will find that some of the options in Siril work better for some types of images and other options for other types. It is a very powerful tool, but it takes some messing about with to get your legs under you. Then too, most of the image software is like that. I'm trying to wrap my head around StarTools myself....been using GIMP, and it is OK, but there are things I do in multiple steps that other programs make a single-step. Good job getting rid of the noise!
  4. A few things I noticed: The focus was a bit out, and the tracking was slipping, frame to frame and there was a lot of noise at varying levels frame to frame, including some light from a source at the lower left of each frame. These are things that make it a bit more difficult and can be corrected with effort and practice. Several frames had to be excluded in the selection process, including one frame with a satellite trace across the frame. Sometimes satellite traces will "stack out, " but sometimes not. I generally exclude them. This was my Siril recipe (note that I had to exclude about 1/3 of the frames to get a good stack): File Conversion Tab Change directory Add images Sequence name: M51 [Convert] Sequence Tab Sequence export (check Normalize images) FITS (default) [Export sequence] Pre-processing Tab Skip Registration Tab Global Star Alignment (deep sky) Algorithm: Bicubic Check Match stars in selection Check Simplified Drizzle x2 [Go register] I noticed that the sequence created by the registration had some wacky results due to excessive drift in your tracking. I had to go back and exclude those images and re-register. Plot Tab Skip Stacking Tab Stacking Methods: Average stacking with rejection Normalizaton: Additive with scaling Uncheck Force recomputing Check Normilize to 16-bit Rejection: Linear Fit Clipping change [all] to [selected] (too few images to eleminate any now) [Start stacking] The thing that would have made the most difference in this photo would have been the addition of some dark frames and bias frames to get rid of the noise. Many more frames would have been good too. Someone with greater skills than I certainly can do a much better job than this, but in the end, the greatest improvements will be (in order): Focus, Darks & Bias, Tracking and More Images. Much better than My first attempt at M51, however.
  5. When you do the initial load of the images and convert to FITS, two viewers pop up, a composite RGB and a monochrome view from which you can select red, green or blue. What do your images look like in the FITS viewers? As an alternative, you could zip together some of your images and upload them here to let someone else take a whack at the stack. Also, .JPG/.JPEG is not a great format for images. Use FITS, TIFF or something else for your capture. You lose a lot with .jpg compression....it is ok for the final image, and great for posting on the web, but not much good for other uses. Or, at least, not as good as some other options.
  6. I use Siril, but I didn't like it at first. There's a learning curve, but one you figure out what it wants, it works very well.
  7. I have a SV105. Best to set it at 1080p (1920x1080). That way, if you scale down the image, say, to 640, you get a much sharper image. I have gotten some really good results with the 105, that I demoted to guide scope after I got the 305. Looking at the image of Jupiter you show, It looks to me like you stacked it without doing a registration in your stacking program, making the stacked images not completely lined up. This is my first moon shot with the SV105, shot at 1920x1080 and reduced to 640:
  8. I've been doing a lot of beta testing with software of late, ever trying to optimize my setup and help where I can as new "stuff" is available. Lots of good stuff, but alas, all the reconfiguration and adaptations has my setup in a bit of disarray. Last night, we had one of the first really clear nights we have had in recent memory. So, let's put the scope outside and brave the mosquitoes! Maybe grab a few Messier objects we haven't managed yet.... Well, not so much. Some of the new tracking software betas didn't exactly hold tracking without a guide scope (I really have to start using one). I switched to another "stable" version, and had similar luck, so I undid everything and went back to the Android Tablet driving SynScan. Depending on where you are looking, drift can be a problem, but it can usually find a deep sky object with a decent alignment. Well again, not so much. It was getting late and we still didn't have an image, so we opted for the Anglefish Globular Cluster, as it was in a good spot and fairly bright. Only a real dumbbell could mess that up, right? I did manage to find a smudgy gray image in the finder scope, not quite where I though it should be, but close. When I realized what it was, I had to take a few pictures. Drift was pretty bad on the mount driven by Synscan, so I couldn't get long exposures. I didn't even bother to get darks because I knew that it wouldn't stack well. The lesson here is, don't be a dumbbell! If your stuff is working, don't mess with it!
  9. I have been doing some beta testing with my SV305 and new drivers. Still a bit unsteady as I move forward into the dark. I thought this was fair for a first attempt. I was pleased to get the shadow of one of the moons (just about 2 o'clock from center as a blueish area).
  10. I usually shoot 10 second exposures, but I get lots and lots and lots of subs. While I do recognize that 100 10 second subs does not equal 10 10 minute subs, it probably comes close to half the light of a long exposure collection. After stacking, I get pretty good light density....and all but eliminate the shortcomings of my Alt/Az tracking.
  11. It has been a while since I worked on instruments. To make an -actual- living, I left the music business and did software development some years ago. Although, I still perform a bit, though on pedal steel. Pedal steel players not only "get" to sit down during a gig, they "must" sit down. My second choice would be Bass sax. At least most of them have wheels.
  12. I spend the first 20 years or so of my working life repairing musical instruments....can't even say how many saxophones I have overhauled. Everything from sopraninos to bass.
  13. Synscan has two or three tracking modes. Make sure you change to LUNAR from SIDEREAL tracking for moon shots. Tracking still isn't going to be perfect on an Alt/Az mount, but it will be better with the right tracking. Stacking may help, but that looks like simple focus. It is normal for a camera to have a different focus point from a given optical lens. However, if you cannot focus your camera somewhere between full focus-in to full focus-out, you may need an extension tube to move the camera farther out (always assuming the camera and telescope are a proper match and don't require some wacky adapter to begin with). While it is normal for atmospherics to mess with moon clarity, you should be able to get a crisper image than the one shown.
  14. I found some ASTAP videos on Youtube. From a cursory examination, I'd say that while it does stacking that would be acceptable for astrophotography, its primary focus is as an annotation and research tool. It has loads of features for identifying comets, asteroids and other objects and allows one to ignore the whole image stacking and stack single moving objects (such as a comet), relegating the stars, galaxies and such to star trails. If I have it right, its primary stacking method is to plate solve each image, rather than seeking pixel patterns. Apparently, it then uses pixel patterns for the target in the images and combines the plate solve coordinates with the target coordinates for its selective stacking. Very cool, and useful for research, but not particularly optimal for artwork. I may keep it in the toolbox for its annotation abilities, but I don't think its a good fit for artful attempts.
  15. Anyone using ASTAP for stacking? I installed it to take a look. Good feature set, but the UI isn't exactly self-explanatory. I'm wondering now if it worth the time to explore. I mean, I'd have to read instructions and stuff just to get a start.
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